Phototherapy light engine

ABSTRACT

Described herein are devices, systems, and methods for delivering phototherapy to a subject. A phototherapy light engine is combined with other components to form a phototherapy system that provides phototherapy treatment to a subject. A phototherapy system may be implemented as a hand held system comprising the light engine that is configured to communicate with a remote computing device.

CROSS-REFERENCE

This application is a continuation of U.S. patent application Ser. No.15/839,678 filed on Dec. 12, 2017, which is a continuation of U.S.patent application Ser. No. 15/351,119, filed on Nov. 14, 2016, now U.S.Pat. No. 9,901,747, issued Feb. 27, 2018, which is a continuation ofInternational Application No. PCT/US2016/024996, filed on Mar. 30, 2016,which claims the benefit of U.S. Provisional Application Ser. No.62/146,124, filed on Apr. 10, 2015, which is herein incorporated byreference in its entirety.

BACKGROUND OF THE INVENTION

Phototherapy is exposure of a subject to either natural sunlight orlight generated by an artificial light source in order to treat alesion, disease, or condition of the subject. Certain wavelengths or arange of wavelengths of light have been found to provide optimal therapyfor particular lesions, diseases or conditions. The UVB range is anexample of a particularly therapeutic range of wavelengths.

Light emitting diodes are a light source that may be used to generatelight in a wavelength range suitable for use with phototherapy. A lightemitting diode comprises a two-lead semiconductor light source, whichemits light when activated. When a suitable voltage is applied to theleads of a light emitting diode, energy is released in the form ofphotons. Modern light emitting diodes may be configured to releasephotons of various wavelengths including wavelengths in the ultravioletrange including wavelengths in the UVB range.

Phototherapy is currently used to treat a range of disorders anddiseases including dermatologic diseases, sleeping disorders, andpsychiatric disorders.

SUMMARY OF THE INVENTION

Described herein are devices, systems, and methods that deliver lightfor phototherapy to a subject. The devices, systems, and methodsdescribed herein are adapted for delivery of phototherapy in terms oftheir mode of delivery of phototherapy, uniformity of light administeredto a treatment site, the power of the photo-output that is achievable,and the relatively low cost of production, among other things.

The mode of delivery described herein is adapted in that the devices,systems, and methods described herein may be implemented with ahand-held device. Traditional phototherapy providing devices are largeand cumbersome, and are thus not suitable for hand held use. Hand helduse is advantageous because, for example, it is a convenient mode interms of ease of use for the subject, and hand held use is additionallyadvantageous because, for example, hand held use allows a subject todirect therapy directly to an area requiring treatment. Hand held usageis achievable, in part at least, due to the suitability of use of lightemitting diodes in providing phototherapy. Light emitting diodes have avery small die size which is typically less than 1 square millimeter.Individually packaged light emitting diodes are also small having a sizethat is typically less than 15 square millimeters. Light emitting diodesalso have the advantage that they can be driven with low voltageelectronics that reduces the size of the power electronics and enablesthe device to be easily driven with a battery-powered supply. The smallsize of light emitting diodes allows the use of the light emittingdiodes in arrays that are themselves relatively small in diameter or insize, and can be combined with other relatively small components to forma unique phototherapy device adapted for hand held use.

The power of the photo-output that is achievable is also adapted in thedevices, systems, and methods described herein. An improved photo-outputis advantageous because, for example, it may be expected to decreasetreatment time, thus increasing treatment compliance, and is alsoadvantageous because, for example, it may provide a more cost effectivetreatment. The improved power output is achieved, at least in part, dueto the use of thermal control in combination with the use of multiplereflectors and reflector types. It is common for light emitting diodeoutput to drop dramatically as the temperature of the light emittingdiode increases. In some cases this output can drop below 50% of theachievable power just from self-heating. Furthermore, controlling thetemperature rise may permit the devices described herein to drive lightemitting diodes at higher power levels without suffering efficiencylosses associated with higher operating temperatures. Additionally,utilizing reflectors may permit the devices described herein to directthe emitted light to the target area with improved efficiency. Lightemitting diodes typically output light in all directions and in somecases more than 50% of the emitted light may be lost from absorptioninto surrounding materials without the use of reflectors.

The systems and devices described herein are also adapted in terms ofcost of production. High cost is generally a barrier to entry in thephototherapeutics market. A lower cost of production is advantageousbecause, for example, it will allow the device to be provided for homeuse at an affordable cost. The reduction of cost is achievable, at leastin part, because the efficiency gains from the use of thermal controland reflectors allows for a reduction in the number of LEDs for lightemissions required for phototherapy.

Specifically, described herein is a phototherapy light engine devicecomprising a thermally conductive core substrate having a first and asecond surface, a plurality of light emitting diodes configured tocouple with said first surface of said thermally conductive metal coresubstrate, a plurality of light reflectors coupled to said first surfaceof said thermally conductive metal core substrate, a collar coupled tosaid first surface of said thermally conductive core substrate, a windowcoupled to said collar and positioned to cover at least part of saidthermally conductive core substrate, and a heat sink coupled to saidsecond surface of said thermally conductive metal core substrate.

Also described herein is phototherapy system comprising a light enginewhich comprises a thermally conductive core substrate and a plurality oflight emitting diodes configured to couple to said thermally conductivecore substrate, along with one or more current drivers configured todrive said plurality of light emitting diodes, a microprocessor coupledto said current driver, wherein said microprocessor controls saidcurrent output of said current driver, a user interface coupled to saidmicroprocessor, wherein said user interface is configured to providesaid user with control over said plurality of light emitting diodes, anda wireless receiver coupled to said microprocessor.

Also described herein is a method for thermally compensating aphototherapy device, said method comprising providing a phototherapysystem to a subject comprising a thermally conductive core substratecoupled to a plurality of light emitting diodes along with a thermistorthat is either thermally or physically coupled to said thermallyconductive core substrate, a microprocessor that is either coupled withor comprises a retrievable data storage memory, and recording, with saidthermistor, temperature data during operation of said phototherapysystem. The method also comprises adjusting, with said microprocessor,based on said temperature data, at least one of a duration of lightemission from said plurality of light emitting diodes and an amount ofpower supplied to said plurality of light emitting diodes and storing,using said retrievable data storage memory, said temperature data.

INCORPORATION BY REFERENCE

All publications, patents, and patent applications mentioned in thisspecification are herein incorporated by reference to the same extent asif each individual publication, patent, or patent application wasspecifically and individually indicated to be incorporated by reference.

BRIEF DESCRIPTION OF THE DRAWINGS

The novel features of the devices, systems, and methods described hereinare set forth with particularity in the appended claims. A betterunderstanding of the features and advantages of devices, systems, andmethods described herein will be obtained by reference to the followingdetailed description that sets forth illustrative embodiments, in whichthe principles of the invention are utilized, and the accompanyingdrawings of which:

FIG. 1A shows an oblique frontal view of an embodiment of a phototherapysystem described herein.

FIG. 1B shows an oblique top view of an embodiment of a phototherapysystem described herein.

FIG. 2 shows an oblique top view of an embodiment of a light enginedescribed herein.

FIG. 3 shows a schematic of a frontal cross section of an embodiment ofa light engine.

FIG. 4 shows an exploded view of an embodiment of a light enginedescribed herein.

FIG. 5 is a schematic top view of a thermally conductive core substratedescribed herein.

FIG. 6 is a schematic representation of components that combine with thelight engine device to form a phototherapy system described herein.

FIG. 7 is a schematic representation of a method for using devices andsystems according to embodiments described herein.

DETAILED DESCRIPTION OF THE INVENTION

Described herein are devices, systems, and methods for providingphototherapy to a subject. Before explaining at least one embodiment ofthe inventive concepts disclosed herein in detail, it is to beunderstood that the inventive concepts are not limited in theirapplication to the details of construction, experiments, exemplary data,and/or the arrangement of the components set forth in the followingdescription, or illustrated in the drawings. The presently disclosed andclaimed inventive concepts are capable of other embodiments or of beingpracticed or carried out in various ways. Also, it is to be understoodthat the phraseology and terminology employed herein is for purpose ofdescription only and should not be regarded as limiting in any way.

In the following detailed description of embodiments of the describedsubject matter, numerous specific details are set forth in order toprovide a more thorough understanding of the inventive concepts.However, it will be apparent to one of ordinary skill in the art thatthe inventive concepts within the disclosure may be practiced withoutthese specific details. In other instances, well-known features have notbeen described in detail to avoid unnecessarily complicating the instantdisclosure.

Further, unless expressly stated to the contrary, “or” refers to aninclusive or and not an exclusive or. For example, a condition A or B issatisfied by any one of the following: A is true (or present) and B isfalse (or not present), A is false (or not present) and B is true (orpresent), and both A and B are true (or present).

In addition, use of the “a” or “an” are employed to describe elementsand components of the embodiments herein. This is done merely forconvenience and to give a general sense of the inventive concepts. Thisdescription should be read to include one or at least one and thesingular also includes the plural unless it is obvious that it is meantotherwise.

The term “subject” as used herein may refer to a human subject or anyanimal subject.

Finally, as used herein, any reference to “one embodiment” or “anembodiment” means that a particular element, feature, structure, orcharacteristic described in connection with the embodiment is includedin at least one embodiment. The appearances of the phrase “in oneembodiment” in various places in the specification are not necessarilyall referring to the same embodiment.

Described herein are devices, systems, and methods for providingphototherapy to a subject. In an embodiment, a phototherapy devicecomprises a light engine. A light engine comprises one or more lightemitting diodes configured to deliver phototherapy to a subject.

In an embodiment a light engine comprises one or more light emittingdiodes coupled to a thermally conductive core substrate. The thermallyconductive core substrate may comprise metal or a non-metal material. Inan embodiment, a thermally conductive core substrate comprises aluminum.Other non-limiting examples of metals suitable for use as a thermallyconductive metal core substrate comprise copper, gold, iron, lead,nickel, silver, and titanium as well as alloys of these metals with eachother and any other metal or metals. In an embodiment, a thermallyconductive material comprises ceramic. In an embodiment the thermallyconductive core substrate is approximately 1 mm in thickness. In anembodiment the thermally conductive core substrate thickness is in therange of 0.5 mm to 5 mm. In an embodiment the thermally conductive coresubstrate thickness is in the range of 0.5 mm to 10 mm. In an embodimentthe thermal conductivity of the substrate is in the range of 1 W/mK to 5W/mK.

In an embodiment, one or more light emitting diodes are coupled with athermally conductive core substrate. A plurality of light emittingdiodes may comprise, for example, at least one bare die light emittingdiode. A plurality of light emitting diodes may entirely comprise, forexample, non-bare die light emitting diodes. A plurality of lightemitting diodes may entirely comprise, for example, bare die lightemitting diodes. A bare die light emitting diode comprises a lightemitting diode that is free from additional packaging typically usedwith light emitting diodes. An exemplary benefit of a bare die lightemitting diode, in comparison to a non-bare die light emitting diode, isthe absence of material that inhibits thermal conduction to the LEDjunction. Other exemplary benefits of a bare die light emitting diode,in comparison to a non-bare die light emitting diode, is improved energyefficiency and the absence of thermal limitation associated with typciallight emitting diode packaging. Another exemplary benefit of a bare dielight emitting diode, in comparison to a non-bare die light emittingdiode, is the absence of materials that reduce or constrain the opticaloutput of the LED. In an embodiment, a plurality of light emittingdiodes are arranged in an array on a surface of a thermally conductivecore substrate. In an embodiment, a plurality of optically transmissivecovers are positioned in direct contact with said light emitting diodeswithout an air gap, for reducing optical losses from internal refractionbetween said light emitting diodes and air. In an embodiment thetransmissive covers are composed of silicone or a formulation based onsilicone.

In an embodiment, one or more light emitting diodes is/are directlycoupled to a thermally conductive core substrate. A light emitting diodemay be directly coupled to a thermally conductive core substrate by, forexample, soldering of the light emitting diode directly to the thermallyconductive core substrate. In other embodiments the light emittingdiodes are attached with a conductive epoxy or fused by using asintering process.

In an embodiment, one or more light emitting diodes is/are coupled tocontact pads which are in turn coupled to a thermally conductive coresubstrate. In an embodiment, the contact pads are separated from thethermally conductive core substrate by a thin dielectric layer forelectrically insulating the contact pads from the thermally conductivecore substrate.

In an embodiment, a contact pad has an area that is substantially widerand/or larger than the area of a light emitting diode. An exemplarybenefit of large contact pad area is to provide a larger area for heatto transfer from the contact pad through the dielectric medium to thethermally conductive core substrate. In this embodiment, heat generatedby the light emitting diode is dispersed through the surface of thecontact pad rather than being transferred directly from the lightemitting diode to the thermally conductive core substrate.

In an embodiment, a contact pad comprises a thermally conductive metal.Non-limiting examples of metals suitable for use as thermally conductivemetal comprise copper, tin, gold, iron, lead, nickel, silver, andtitanium as well as alloys of these metals with each other and any othermetal or metals.

In an embodiment, the area of a contact pad is about 6 squaremillimeters, or approximately 50 times the contact area on the lightemitting diode. In an embodiment, the area of a contact pad is about 10square millimeters. In an embodiment, the area of a contact pad is about9 square millimeters. In an embodiment, the area of a contact pad isabout 8 square millimeters. In an embodiment, the area of a contact padis about 7 square millimeters. In an embodiment, the area of a contactpad is about 5 square millimeters. In an embodiment, the area of acontact pad is about 4 square millimeters. In an embodiment, the area ofa contact pad is about 3 square millimeters. In an embodiment, the areaof a contact pad is about 2 square millimeters. In an embodiment, thearea of a contact pad is about 1 square millimeter.

In an embodiment, a plurality of light emitting diodes are arranged in aplurality of strings. Each string of light emitting diodes may, forexample, be driven separately, or, for example, the current in eachstring may be matched. In an embodiment, the drive current of eachstring is adjusted independently to improve the optical uniformity atthe output of the light engine.

In an embodiment, one or more light emitting diodes is/are positioned sothat they are recessed back relative to a phototherapy target area to betreated. Recessed light emitting diodes produce light that mixestogether within the recessed space before being delivered to a, forexample, targeted skin surface. In another embodiment, the lightemitting diodes are arranged approximately equidistant to one another,to produce light of uniform intensity on the targeted surface. Inanother embodiment reflectors are positioned and angled in a manner toproduce light of uniform intensity on the targeted surface.

In an embodiment, a light engine further comprises one or morereflectors. The one or more reflectors may comprise a reflective metalsuch as, for example, aluminum. The one or more reflectors may comprisea material coated with a reflective coating. The reflectors may, forexample, comprise a polymer with an aluminum film deposited on thesurface.

In an embodiment, one or more cone shaped reflectors have a one to onerelationship with one or more light emitting diodes, wherein each lightemitting diode on the surface of the thermally conductive substrate ispositioned inside of a cone shaped reflector. Alternatively oradditionally, a plurality of light emitting diodes may be positionedinside an area with reflectors at the perimeter.

In an embodiment, a plurality of cone shaped reflectors are connected toeach other, forming a single unit having a shape and configurationsimilar to an egg carton.

In an embodiment, a light engine further comprises a housing, whereinthe housing has at least one opening or aperture. In an embodiment, thethermally conductive core substrate is positioned within the housing andis recessed relative to the opening or aperture on the housing so thatthe light emitting diodes are recessed relative to the opening oraperture. The interior walls of the housing may be lined withreflectors. The interior walls of the housing may comprise reflectors.The interior walls of the housing may comprise a reflective coating.Reflectors on the interior surface of the housing may be positionedperpendicularly to the thermally conductive core substrate, or,alternatively reflectors may be positioned at an angle to the thermallyconductive core substrate.

In an embodiment, a light engine further comprises a window positionedin the opening or aperture of the housing. In an embodiment, the windowis positioned and sized so that it covers the entire array of lightemitting diodes. The window may comprise, for example, acrylic. Thewindow may comprise, for example, fused silica. In an embodiment, thewindow is UV transmissive.

In an embodiment, the window comprises a filter of light so that onlylight within a specific range is transmissive. For example, a window inthis embodiment may be configured to be transmissive to light in the UVBwavelength. For example, a window in this embodiment may be configuredto be transmissive to light having a wavelength in the range of 300-320nanometers. In an embodiment, the window is attenuative to light outsideof a desired wavelength. In this embodiment, attenuation may be achievedby, for example, coating the window with an absorptive optical coating.Alternatively, the attenuation may be achieved by a series of opticalinterference coatings. Alternatively or additionally, in thisembodiment, the material of the window may be selected for filteringqualities that are innate to the material. Alternatively oradditionally, in this embodiment, the thickness of the window may beselected for filtering qualities related to material thickness.

In an embodiment, a light engine further comprises a collar whichdefines a treatment area on, for example, a skin surface of a subject. Acollar extends above the window so that the window is never in directcontact with the subject, but rather the collar is configured to be ableto come into contact with the skin surface of a subject when contactwith the skin surface of a subject is desired for effective treatment.In an embodiment, a collar extends directly from the walls of thehousing, wherein the window is positioned within the housing so that thewalls of the housing extend beyond the window. In an embodiment, thecollar comprises the same material as the housing. In an embodiment, acollar comprises a soft, biocompatible material, for example, silicone.In an embodiment, a collar comprises a flexible material that conformsto body contours. In an embodiment, the collar defines the area overwhich the light emitted by the light emitting diodes is delivered. In anembodiment, the collar comprises a thin wall for reducing the importanceof distinguishing between the treatment area defined by the inner walland the perceived treatment area defined by the outer wall. In anembodiment, the collar is shaped as a square or rectangle in order tofacilitate uniform treatment of an area that is larger than thetreatment area defined by the collar, wherein a subject is able to movethe device after each area is treated so that the rectangular or squareshaped treated areas conveniently align with each other to cover theentire area to be treated. In an embodiment, a collar may be lined withreflectors. The collar may comprise reflectors. The collar may comprisea reflective coating. In an embodiment, reflectors on the interiorsurface of the collar are positioned at an angle that optimally deliversa uniform column of light, emitted by one or more light emitting diodes,through the window. In an embodiment, the collar comprises or is coupledto one or more sensors that indicate when the collar (and thus thedevice) is in contact with the skin. In this embodiment, a signal fromthe sensor, indicating contact with the skin, may cause the device toenable phototherapy, and a signal that indicates that the device is nolonger in contact with the skin may cause the device to disablephototherapy. In an embodiment, the sensors are mechanical switches thatare activated by depressing the collar.

In an embodiment, a light engine comprises a heat sink. In anembodiment, a heat sink is positioned on the surface of the thermallyconductive core substrate that is opposite to the surface of thethermally conductive core substrate to which one or more light emittingdiodes is/are coupled. The heat sink is configured to exchange heat tothe environment through conduction. The heat sink, may, for example,comprise a thermally conducting material such as a thermally conductivemetal such as, for example, aluminum. The heat sink may also, forexample, comprise a thermally conductive plastic. In an embodiment, theheat sink is coupled to the enclosure. In another embodiment, the heatsink forms part of the enclosure. In an embodiment, a thermal compoundis applied between the thermally conductive metal core substrate and theheat sink to aid in thermal coupling. In an embodiment, the heatsink ispositioned within the thermally conductive core substrate and comprisesa phase change assembly commonly known as a heat pipe.

In an embodiment, a heat sink is coupled to a fan which is positioned onthe surface of the heat sink which is opposite to the surface facing thethermally conductive core substrate.

Also described herein is a phototherapy system which comprises a lightengine coupled with one or more additional components. The one or moreadditional components may comprise a microprocessor, a computer readablestorage medium comprising a retrievable memory, a current driver, agraphic user interface comprising or coupled with a display, athermistor, a transmitter, and a receiver.

A current driver may comprise multiple channels such that the currentdriver is configured to individually drive separate strings of lightemitting diodes. It may be desirable to separate light emitting diodesinto strings to limit the voltage required to drive the string or toallow for an adjustment mechanism to improve uniformity of lightemissions at the output of the system. In an embodiment, a currentdriver is configured to match the currents driven through each of themultiple channels. In an embodiment, a current driver is configured todetect short circuits or open circuits within a string of light emittingdiodes. In an embodiment, the drive current of each string is separatelyadjustable to facilitate optimization of light emission uniformity.

A user interface may comprise a display. A user interface mayalternatively or additionally comprise buttons, switches, or toggles. Inan embodiment, a user may initiate a stored treatment or sequence oftreatments using the user interface. A treatment may, for example,comprise a dose or duration of phototherapy intended for a treatmentsite. In an embodiment, the display shows a user the current treatmentsite and time remaining for the treatment.

A transmitter is configured to wirelessly transmit data to a computingdevice. Non-limiting examples of wirelessly transmitted signals maycomprise, for example, an RF signal, an ultrasound, a Wi-Fi™ signal, ora Bluetooth™ signal. In an embodiment, the transmitter transmits awireless signal comprising treatment data. Treatment data may comprise aregimen administered to a subject. Treatment data may alternatively oradditionally comprise schedule data, which may comprise, for example,dates in which a subject previously received phototherapy via the lightengine. A computing device that receives a wirelessly transmitted signalfrom the light engine may comprise a remote server. A computing devicethat receives a wirelessly transmitted signal from the light engine maycomprise a mobile computing device such as, for example, a smartphone,tablet computer, or laptop computer.

A receiver is configured to receive wireless data from a computingdevice. Non-limiting examples of wirelessly received signals maycomprise, for example, an RF signal, an ultrasound, a Wi-Fi signal, or aBluetooth signal.

Wireless data received may comprise prescribed treatment sites anddoses, configuration information and other program information. Forexample, a wirelessly received communication could enable the deviceuser interface for a prescribed treatment sequence.

A thermistor may, for example, be coupled to the thermally conductivemetal core material. A “thermistor”, as the term is used herein, mayrefer to any temperature measurement device which could be a thermistor,resistance temperature device, thermocouple or temperature measurementintegrated circuit. A thermistor measures temperature that represents,for example, the temperature of the thermally conductive metal corematerial or the light emitting diodes. The light emissions of the lightemitting diodes are directly related to the power driven through thelight emitting diodes and the temperature of the light emitting diodes.The temperature of the light emitting diodes may be measured by thethermistor and communicated to the microprocessor.

In an embodiment, a phototherapy system may further comprise an opticalpower measurement device positioned between a plurality of lightemitting diodes and an optical window for measuring and calibratinglight emissions.

The microprocessor may be coupled to other components including but notlimited to the current driver, the display, the user interface, athermistor, and a wireless transmitter and a receiver. Themicroprocessor may be coupled to other components in such a way thatallows both one and two way communication between the microprocessor andthe other components. A communication from a microprocessor to a currentdriver may, for example, pass current through a channel. A communicationfrom a current driver to a microprocessor may, for example, may identifya detected short circuit or open circuit. In an embodiment, a signalcommunicated from the microprocessor to the current driver may turn thecurrent driver on or off. In an embodiment, a microprocessor may causethe display to guide the user through a sequence of treatments. A userinterface may provide a subject controls to initiate treatment commandsto the microprocessor. In an embodiment, a microprocessor receivestemperature data from a thermistor.

In an embodiment, the system output is calibrated by measuring theoptical output and temperature of the system over the range of operationof the system and storing this calibration information in the devicememory. In another embodiment, the system output is calibrated bymeasuring the optical output and temperature of the system at one ormore operating temperatures and using known performance information tofill in the output table. In another embodiment, the temperaturemeasured by the thermistor is used by the microprocessor to adjust thetreatment time in accordance with known or measured outputcharacteristics of the light engine. For example, if the system iscalibrated to output 100 mW at a thermistor temperature of 40 C, and 90mW at a thermistor temperature of 45 C, then a 60 second treatmentintended for 100 mW of power at 40 C would run for 66 seconds on awarmer day where the thermistor temperature read 45 C.

In an embodiment, a microprocessor causes data to be transmitted throughthe wireless transmitter, which may, for example, comprise subject ortreatment data. In an embodiment, information that is received by thereceiver is communicated to the microprocessor, wherein the receivedsignal may comprise, for example, a program of therapy conditions to beadministered. The microprocessor may be configured to code or decodetransmitted and received signals. For example, subject information ortreatment data may be coded or decoded by a microprocessor in order to,for example, protect patient private data. In an embodiment, a receivedcommand comprises a signal that is processed by the microprocessor. Acommand may comprise, for example, a signal to shut off current flow toone or more light emitting diodes or one or more light emitting diodestrings. A microprocessor may comprise or be coupled to a computerreadable storage medium comprising a memory. A computer readable storagemedium may store, for example, subject identification data, therapydata, or performance data.

In an embodiment, data received by a receiver comprises data that wasgenerated by another phototherapy device or a population of phototherapydevices. For example, optical performance data from a population ofphototherapy devices may be received, communicated to themicroprocessor, and then used by the microprocessor to make adjustmentssuch as, for example, adjustments to compensate for LED outputdegradation over time under certain use conditions.

In an embodiment, a phototherapy system is powered by one or morebatteries. In an embodiment, the battery voltage is boosted to supplypower to a string of light emitting diodes. In an embodiment, batterypowered light engine comprises a hand held device. The one or morebatteries used in the light engine may be rechargeable batteries.

In an embodiment, a phototherapy system couples with a charging port ordocking station configured to recharge the one or more rechargeablebatteries when the charging port and light engine are coupled. In anembodiment, a docking station further comprises optical powermeasurement device for measuring and calibrating light emissions.

FIGS. 1A and 1B show a graphic representation of an embodiment of alight engine 100 according to an embodiment described herein. The deviceshown in FIGS. 1A and 1B comprises a hand held device 100. FIG. 1A is anoblique frontal view of the device 100. FIG. 1A shows a window 102. Thewindow 102 is positioned within an opening in the housing of the device100. The window 102 is positioned so that it covers the light producingarea of a thermally conductive core substrate coupled with one or morelight emitting diodes (not shown). The window 102 may be configured tofilter or attenuate light wavelengths that are not therapeutic.Similarly, the window 102 may be configured to be highly transmissive oflight at a desired wavelength such as, for example, light within therange of wavelengths of 300-320 nanometers. A cone shaped reflector 104may be part of a single unit of other cone shaped reflectors. In theembodiment shown in FIG. 1A, there are sixteen total cone shapedreflectors, including cone shaped reflector 104, that are connected in afashion similar to an egg carton. At least one light emitting diode (notshown) is positioned within each one of the cone shaped reflectors. Acollar 106 that is fitted around the entire opening of the housing ofthe device 100 extends beyond the window 102. The collar 106 maycomprise a compressible material that is configured to conform to fitcurved body surfaces and also suitable to comfortably come into contactwith the skin surface of a subject when contact with the skin surface ofa subject is desired for effective treatment. When used to, for example,treat an area of a subject's skin, the device 100 is configured to beheld against an area of skin of the subject in such a way that the outeredges of the collar 106 directly contact the subject's skin. That is tosay, the subject (or someone else) holds the device 100 against thesubject's skin so that the collar 106 contacts the skin of the subjectin a way that positions window 100 directly over the target area (i.e.the treatment area). Once held over the area of the skin to be treated,light emitted by the light emitting diodes (not shown) passes throughthe window 102 to reach the skin area to be treated. The collar 106 maycomprise reflectors on its interior surface or a reflective coating.When the device 100 is held in contact with the skin surface of asubject the collar 106 defines the surface area of treatment, whereinthe area that is treated essentially comprises the same area defined bythe borders of the collar 106. FIG. 1B shows a top view of device 100.Display screen 108 may comprise a digital display that may be coupled toa user control to form a graphical user interface. User control 112 isshown in FIG. 1B as a start switch. However, as described hereinnumerous other embodiments of user control 112 are suitable for usealong with the systems, devices, and methods described herein. Thehandle 110, as shown in FIG. 1B, provides a subject or another with aconvenient way to hold the device 100 while positioning the device 100in contact with a skin surface of the subject.

FIG. 2 shows an embodiment of an oblique overhead view of a light enginedevice 200 according to an embodiment described herein. Window 202 ispositioned over the light emitting diodes (not shown), the thermallyconductive substrate material (not shown), and reflector cones(including the reflector cone 204). In this embodiment, reflector cone204 is part of a larger unit that includes other interconnectedreflector cones. A heat sink 214 is positioned underneath the thermallyconductive substrate material (not shown), and reflector cones(including the reflector cone 204). The heat sink 214 passively conductsheat away from the light emitting diodes and thermally conductivesubstrate material when the device is operated. In this embodiment, theheat sink 214 is coupled to a fan 216 (fan housing is shown) which ispositioned directly below the heat sink 214. The fan 216 functions toactively cool the device including the light emitting diodes andthermally conductive substrate material. The fan 216 may be powered by abattery or other power source (not shown) that powers the device 200.

FIG. 3 shows a schematic of a frontal cross section of an embodiment ofa light engine device 300 according to an embodiment described herein.Collar 306 extends beyond window 302. The collar 306 may comprise or becoupled with reflector 328. The reflector 328 extends continuously fromthe interior wall of the housing of the device 300 to beyond the window302 along with the collar 306. The collar 306 may also comprise or becoupled with contact sensor 330 that transmits a signal when the collar306 contacts a skin surface of a subject. A thermally conductive coresubstrate 318 is positioned below an array of light emitting diodes(including light emitting diode 324) and the cone reflectors (includingcone reflector 326). A heat sink 320, as described herein, is positionedbelow the thermally conductive core substrate 318. A fan 322, asdescribed herein, is positioned below the heat sink 320.

FIG. 4 shows an exploded view of an embodiment of a light engine device400 according to an embodiment described herein. A collar 406 is shownwith a frame fitting around window 402. A window spacer 432 with areflective interior surface separates a window 402 from reflector cones404. The window spacer 432 provides a space between an array of lightemitting diodes and the window 402, such that the light emitting diodesare recessed relative to a targeted treatment site. Light emitted fromrecessed light emitting diodes is focused within the space provided bythe window spacer 432 by the reflectors on the interior surface of thewindow spacer 432 as well as the cone shaped reflectors 404. Providing aspace in which to focus the light from the one or more light emittingdiodes in an array of light emitting diodes provides that the light thatis delivered by the device is homogenous at the level of the targetedtreatment site. A portion of the device housing may comprise windowspacer 432 as described herein. A thermally conductive core substrate418 as described herein is positioned between the cone shaped reflectors404 and the heat sink 420. Heat sink 420 and fan 422 are shownpositioned respectively beneath the thermally conductive core substrate418 as described herein.

FIG. 5 is a schematic top view of a thermally conductive core substrate518 according to an embodiment described herein. One or more lightemitting diodes 534 are positioned on a contact pad 536 as describedherein. The light emitting diodes on the surface of the thermallyconductive core substrate 518 may form an array. There may be one lightemitting diode 534 per contact pad 536, or alternatively a lightemitting diode 534 may be positioned on multiple contact pads 536. Athermistor 538, as described herein, is shown positioned on thethermally conductive core substrate 518. The thermistor 538 may bepositioned in the center of the thermally conductive core substrate 518as shown or at another position relative to the thermally conductivecore substrate 518.

FIG. 6 is a schematic representation of components that combine with thelight engine device described herein to form a phototherapy system. Amicroprocessor 650, as described herein, may comprise or be coupled witha computer readable medium 646 comprising a memory. A computer readablemedium 646 is configured to store software and data. Software stored onthe computer readable medium 646 may be executed by the microprocessor650, and may define how the microprocessor affects other components,such as, for example, a graphic user interface 640, or, for example, acurrent driver 644. Data stored on the computer readable medium 646 maycomprise subject identifying information or treatment information. Agraphic user interface 640 may further comprise or be coupled with adisplay 642. The microprocessor 650 may be configured to control theoutput on the display 642. Data and commands inputted by a subject intothe graphic user interface 640 are transmitted to the microprocessor650. Similarly, as described herein, the microprocessor 650 bothcontrols and receives data from the current driver 644. The thermistor648, as described herein, transmits temperature data to themicroprocessor 650. Also, as described herein, receiver 652 transmitsdata and commands to the microprocessor 650, and, as described herein,microprocessor 650 transmits data to transmitter 654.

FIG. 7 is a schematic representation of a method 700 for using thedevices and systems described herein.

In step 702, a subject is provided with a phototherapy system describedherein comprising a light engine described herein along with theadditional components comprising the microprocessor, computer readablemedium comprising a memory, the graphic user interface and display, thecurrent driver, the thermistor, the receiver, and the transmitter.

In step 704, identifying information entered by a subject is received.Identifying information may comprise, for example, the subject's name,password or personal identification number. A subject may enteridentifying information into the graphic user interface, which is inturn transmitted to the microprocessor and computer readable medium forstorage.

In step 706, one or more of a therapy regimen or other therapeuticinformation is received. A therapy regimen may comprise, for example, aduration of a phototherapy treatment, an intensity of light to bedelivered, or a site to be treated. Therapeutic information maycomprise, for example, a treatment history, a schedule of treatment, orother non-phototherapy treatment instructions. A subject may enter orselect a therapy regimen or therapeutic information through the graphicuser interface. A subject may select and activate a therapy regimenusing the graphic user interface, wherein the therapy regimen, forexample, comprises phototherapy duration or intensity, which is in turntransmitted to the microprocessor and computer readable medium forstorage. Alternatively or additionally, a therapy regimen or therapeuticinformation may be received from a remote computing device such as, forexample, a therapy regimen or therapeutic information transmitted thereceiver by a remote health care provider.

In a step 708, a subject is instructed to hold the phototherapy systemdescribed herein in contact with a targeted treatment area.

In step 710, a contact sensor transmits a signal to the microprocessorwhen the contact sensor contacts a skin surface of a subject. A signalreceived from the contact sensor indicating that the phototherapy systemdescribed herein is in contact with the skin surface of a subject causesthe microprocessor to enable the light engine for phototherapy.

In step 712, phototherapy is administered by, for example, the subjectpressing a start switch and maintaining the phototherapy system incontact with the treatment area until, for example, the displayindicates that the treatment is over. Alternatively or additionally,another person may hold the device for the subject, or a mechanicaldevice can be used to hold the phototherapy system in a fixed positionsuch as, for example, a stand or clamp.

In step 714, the subject is notified that the treatment duration iscomplete. The subject may be notified in a number of ways such as, forexample, an audible sound or a displayed message on a display screen.

In a step 716, the treatment is stopped by the microprocessor once theprescribed treatment time has elapsed. The phototherapy device will alsostop providing therapy if a signal indicating that the device is nolonger in contact with the treatment area is received from the contactsensor.

In step 718, one or more of identifying information or therapeuticinformation is transmitted from the phototherapy system via thetransmitter to a computing device. Therapeutic information may comprise,for example, the duration of treatment, the location treated, or othertreatment related data. The computing device may comprise a remotecomputing device such, as for example, a remote server. Alternatively oradditionally, the computer may comprise a computing device of thesubject such as a laptop, tablet, or smartphone.

In a step 720, a subject transfers the device to another area to betreated until all treatment areas are treated.

While preferred embodiments of the systems, devices, and methodsdescribed herein have been shown and described herein, it will beobvious to those skilled in the art that such embodiments are providedby way of example only. Numerous variations, changes, and substitutionswill now occur to those skilled in the art without departing from thesubject matter described herein. It should be understood that variousalternatives to the embodiments of the systems, devices, and methodsdescribed herein may be employed in practicing the systems, devices, andmethods described herein. It is intended that the following claimsdefine the scope of the invention and that methods and structures withinthe scope of these claims and their equivalents be covered thereby.

What is claimed is:
 1. A phototherapy light engine comprising: a) athermally conductive core substrate having a first and a second surface;b) a plurality of light emitting diodes (LEDs) for emitting lightcomprising phototherapeutic component wavelengths, the plurality of LEDsconfigured to couple with said first surface of said thermallyconductive core substrate, said thermally conductive core substrate forabsorbing heat from said plurality of LEDs; c) a window positioned tocover at least part of said first surface of said thermally conductivecore substrate; d) a collar assembly coupled to said first surface ofsaid thermally conductive core substrate, said collar assemblycomprising a reflective surface on an interior surface of the collarassembly, and said collar assembly adapted to engage the skin surfaceand to limit escape of the emitted light from the skin surface and asurrounding area; e) a heat sink coupled to said second surface of saidthermally conductive core substrate, wherein said heat sink isconfigured and adapted to conduct heat away from said thermallyconductive core substrate; f) a receiver to receive input from a remotecomputing device; and g) a transmitter to transmit performance data ofthe plurality of LEDs.
 2. The phototherapy light engine of claim 1,wherein the plurality of LEDs are arranged in a four by four matrix. 3.The phototherapy light engine of claim 1, further comprising a pluralityof contact pads coupled to at least one of said plurality of LEDs and tosaid first surface of said thermally conductive core substrate, forconducting heat from said plurality of said LEDs to said thermallyconductive core substrate.
 4. The phototherapy light engine of claim 3,wherein the plurality of LEDs are coupled to said plurality of contactpads coupled to said thermally conductive core substrate.
 5. Thephototherapy light engine of claim 3, wherein said plurality of contactpads is separated from the thermally conductive core substrate by a thindielectric layer for electrically insulating said plurality of contactpads from the thermally conductive core substrate.
 6. The phototherapylight engine of claim 1, wherein said plurality of LEDs comprises one ormore bare die LEDs.
 7. The phototherapy light engine of claim 6, furthercomprising a plurality of optically transmissive covers in directcontact with said one or more bare die LEDs without an air gaptherebetween, for reducing optical losses from internal refractionbetween said one or more bare die LEDs and air.
 8. The phototherapylight engine of claim 1, wherein said plurality of LEDs emit light in atherapeutic range comprising a UVB frequency range that is from about300 to about 320 nanometers.
 9. The phototherapy light engine of claim1, wherein said window filters some of the emitted light to block and/orattenuate light in certain wavelengths.
 10. The phototherapy lightengine of claim 1, wherein said remote computing device is a mobilephone, a tablet computer, or a laptop computer.
 11. The phototherapylight engine of claim 1, wherein the reflective surface is positionedinside the collar assembly at an angle that delivers a uniform column oflight.
 12. A phototherapy system comprising: a) a phototherapy lightengine comprising a plurality of light emitting diodes (LEDs) foremitting light comprising phototherapeutic component wavelengths, theLEDs configured to couple to a thermally conductive core substrate forabsorbing heat emitted from said LEDs, wherein light emitted by the LEDsis reflected by a reflective surface positioned on an interior surfaceof a collar assembly of the phototherapy light engine; b) a currentdriver configured to drive said plurality of LEDs; c) a microprocessorcoupled to a multichannel current driver, wherein said microprocessorcontrols said current output of said multichannel current driver; d) anuser interface coupled to said microprocessor, wherein said userinterface is configured to provide said user interface with control oversaid plurality of LEDs; e) a receiver to receive input from a remotecomputing device; and f) a transmitter to transmit performance data ofthe LEDs.
 13. The phototherapy system of claim 12, wherein the pluralityof LEDs are arranged in a matrix arrangement comprising four LEDs alongeach side of the phototherapy light engine.
 14. The phototherapy systemof claim 12, further comprising a plurality of contact pads coupled toat least one of said plurality of LEDs and to a first surface of saidthermally conductive core substrate, for conducting heat from saidplurality of said LEDs to said thermally conductive core substrate. 15.The phototherapy system of claim 14, wherein the plurality of LEDs arecoupled to said plurality of contact pads coupled to the thermallyconductive core substrate.
 16. The phototherapy system of claim 14,wherein said plurality of contact pads is separated from the thermallyconductive core substrate by a thin dielectric layer for electricallyinsulating said plurality of contact pads from the thermally conductivecore substrate.
 17. The phototherapy system of claim 12, wherein saidplurality of LEDs comprises one or more bare die LEDs.
 18. Thephototherapy system of claim 17, further comprising a plurality ofoptically transmissive covers in direct contact with said one or morebare die LEDs without an air gap therebetween, for reducing opticallosses from internal refraction between said one or more bare die LEDsand air.
 19. The phototherapy system of claim 12, wherein said pluralityof LEDs emit light in a therapeutic range comprising a UVB frequencyrange that is from about 300 to about 320 nanometers.
 20. Thephototherapy system of claim 12, further comprising a thermistor coupledto said thermally conductive core substrate, in communication with saidmicroprocessor for measuring temperature of said plurality of LEDsduring operation of said phototherapy system.
 21. The phototherapysystem of claim 12, wherein said remote computing device is a mobilephone, a tablet computer, or a laptop computer.
 22. The phototherapysystem of claim 12, wherein the reflective surface is positioned insidethe collar assembly at an angle that delivers a uniform column of light.